ExxonMobil’s Ranger find in the Stabroek Block is in a league of its own.
A wildcat, the Ranger-1 well is in an area with different geology when compared to other fields where Exxon and its partners have hit the jackpot and offers exciting prospects in that area in the Stabroek Block.
Made in 2018, it was Exxon’s sixth discovery and was its deepest in that year, some 60 miles northwest of the prolific Liza field. Back then, Exxon had only racked up five discoveries, totalling an estimated 3.2 billion recoverable oil-equivalent barrels and Ranger gave the co-venturers better insight into the Stabroek Block’s potential.
Rystad Energy’s Senior Analyst, Sonya Boodoo said back in July 2018 that Ranger could hold some 346 million barrels of oil. Rystad updated this estimate in July 2022 to 432 million barrels. In December 2022, S&P Global Platts provided a new estimate – between 500 and 600 million barrels of oil.
Ranger is in a carbonate play which is more porous when compared to the other discoveries made in sandstone reservoirs.
Carbonates are sedimentary rocks deposited in marine environments and are mostly of biological origin. They are made up of fragments of marine organisms, skeletons, coral, algae, and precipitation, and consist mostly of calcium carbonate, which is chemically active compared to the sand which makes sandstones.
Exploration and evaluation programs for carbonates are like those for sandstone reservoirs. However, according to Schlumberger, new tools, techniques, and interpretation methodologies are required to address the specific challenges above to drill and produce these reservoirs optimally.
Perhaps, it is for this reason, that Exxon is focused on its other Stabroek Block discoveries.
Or perhaps, it is the ongoing Venezuela border controversy.
Recall back in December 2018, Venezuela’s Navy seized the Ramform Tethys, a Petroleum Geo-Services (PGS) company vessel conducting seismic work for Exxon a few miles from the Ranger-1 well.
During a routine patrol, Venezuela’s foreign ministry said its navy had encountered vessels hired by Exxon in an area under “undoubtedly Venezuelan sovereignty” and “proceeded to apply the appropriate international protocols.” In the end, the vessel turned after being told that they did not have jurisdiction to operate there. The area is currently under contention at the International Court of Justice (ICJ).
But Exxon is not the only oil company affected by the border controversy. Occidental Petroleum with the Roraima Block faced a similar hiccup.
In 2012, Anadarko was granted an exploration licence for the Roraima block. A year later, its contracted research vessel MV Teknik Perdana was ordered out of Guyana’s Exclusive Economic Zone by the Venezuelan Navy while conducting a geophysical survey. Anadarko then halted operations in Guyana until July 2015 when it restated interest in drilling for oil in the licensed area.